Featured Research

from universities, journals, and other organizations

Scientists Returning To Field Of Eerie Thermal Spires

Date:

April 17, 2003

Source:

University Of Washington

Summary:

The bizarre hydrothermal vent field discovered a little more than two years ago surprised scientists not only with vents that are the tallest ever seen – the one that's 18 stories dwarfs most vents at other sites by at least 100 feet – but also because the fluids forming these vents are heated by seawater reacting with million-year-old mantle rocks, not by young volcanism.

Share This

The bizarre hydrothermal vent field discovered a little more than two years ago surprised scientists not only with vents that are the tallest ever seen – the one that's 18 stories dwarfs most vents at other sites by at least 100 feet – but also because the fluids forming these vents are heated by seawater reacting with million-year-old mantle rocks, not by young volcanism.

Related Articles

The remarkable Lost City hydrothermal vent field, so named partly because it sits on a seafloor mountain named the Atlantis Massif, was discovered in the middle of the Atlantic Ocean about 1,500 miles off the East Coast of the United States during an expedition that wasn't even looking for hydrothermal vents.

Now the two scientists who were the first to travel in a submersible to the field after its serendipitous discovery Dec. 4, 2000, are leading a National Science Foundation-funded expedition to map and farther investigate the field. A Web site launched today at http://www.lostcity.washington.edu/ will follow the 32-day expedition that starts April 21.

The field is unlike any seen before, according to chief scientist Deborah Kelley, a University of Washington associate professor of oceanography, and co-chief scientist Jeff Karson, a Duke University professor of earth and ocean sciences. Both have visited fields of black-smoker hydrothermal vents that scientists have been studying since the 1970s.

Lost City is distinctive in part because the mighty 180-foot vent at the site, which scientists named Poseidon, is so much larger than previously studied black-smoker vents that mostly reach 80 feet or less. The tallest black-smoker chimney ever seen was a 135-foot vent off the coast of Washington (which toppled in recent years).

In contrast to black-smoker vents that are a darkly mottled mix of sulfide minerals, Lost City vents are nearly 100 percent carbonate, the same material as limestone in caves, and range in color from a beautiful clean white to cream or gray.

The differences are because hydrothermal venting – a process in which water circulates into the seafloor, gaining heat and chemicals until there is enough heat for the fluids to vent back into the ocean – doesn't appear connected to volcanic activity and magma chambers. This is unlike most systems at mid-ocean ridge spreading centers. That's where very young seafloor is created – often dramatically during volcanic eruptions – and vented water can be as hot as 700 F.

Lost City is nine miles from the nearest spreading center and sits on 1.5 million-year-old crust. Heat generated by chemical changes in the rocks appears to drive venting: seawater permeates deeply into the fractured surface of the mantle rocks where it transforms the mineral olivine into a new mineral, serpentine. The heat is not as great as that at volcanically active sites but is enough to power hydrothermal circulation and produce vent fluids of 105 to 170 F.

Lost City vent fluids support a community of microorganisms believed to live off the gases methane and hydrogen, both byproducts of serpentinization. This leads Kelley, Karson and others to speculate that life on this planet may have started in just such an environment, particularly since so much more mantle rock was exposed to seawater early in Earth's history. And the same could be happening on other worlds.

The project includes scientists, engineers and students from the University of Washington, Duke University, Woods Hole Oceanographic Institution, U.S. National Oceanic and Atmospheric Administration, Switzerland's Institute for Mineralogy and Petrology and Japan's National Institute of Advanced Industrial Science and Technology.

The team leaves Barbados April 21 on board the Atlantis, operated by Woods Hole. It takes five days to reach the ocean above Lost City where researchers will use the submersible Alvin and an unmanned Autonomous Benthic Explorer.

Among those on the expedition will be lead pilot Pat Hickey, who took Kelley and Karson in the Alvin to see Lost City the day after it was first spotted during routine surveying using an unmanned, remotely operated vehicle. There was time for just a single dive before the expedition ended and bad weather began so scientists can only say the field is 300 feet by perhaps 1,700 feet and has roughly 30 vent structures. Since then the field has been visited by a U.S. film crew, which conducted no science, and a Russian group, which did limited sampling.

Work this month and next includes studying the waters above the field looking for clues to help find other Lost City fields and visiting a neighboring mountain that looks promising. Researchers also will grow and examine microorganisms recovered from the chimneys.

More From ScienceDaily

More Earth & Climate News

Featured Research

Mar. 3, 2015 — Attendance at schools exposed to high levels of traffic-related air pollution is linked to slower cognitive development among 7- to 10-year-old children in Barcelona, according to a new ... full story

Mar. 3, 2015 — While studying a ground-nesting bird population near El Reno, Okla., a research team found that stress during a severe weather outbreak of May 31, 2013, had manifested itself into malformations in ... full story

Mar. 3, 2015 — Researchers studied quartz from the San Andreas Fault at the microscopic scale, the scale at which earthquake-triggering stresses originate. The results could one day lead to a better understanding ... full story

Mar. 3, 2015 — The 3-D printing scene, a growing favorite of do-it-yourselfers, has spread to the study of plasma physics. With a series of experiments, researchers have found that 3-D printers can be an important ... full story

Mar. 3, 2015 — Researchers have developed a new way of rapidly screening yeasts that could help produce more sustainable biofuels. The new technique could also be a boon in the search for new ways of deriving ... full story

Mar. 3, 2015 — For almost a century, scientists have been puzzled by a process that is crucial to much of the life in Earth's oceans: Why does calcium carbonate, the tough material of seashells and corals, ... full story

Mar. 3, 2015 — Major cities in the UK are falling behind their international counterparts in terms of their use of smart technologies, according to a new study. The research has found that smart cities in the UK, ... full story

Mar. 3, 2015 — To simulate chimp behavior, scientists created a computer model based on equations normally used to describe the movement of atoms and molecules in a confined space. An interdisciplinary research ... full story

Mar. 3, 2015 — Rather than just waiting patiently for any pollinator that comes their way to start the next generation of seeds, some plants appear to recognize the best suitors and 'turn on' to increase the chance ... full story

Featured Videos

Looted and Leaking, South Sudan's Oil Wells Pose Health Risk

AFP (Mar. 3, 2015) — Thick black puddles and a looted, leaking ruin are all that remain of the Thar Jath oil treatment facility, once a crucial part of South Sudan&apos;s mainstay industry. Duration: 01:13
Video provided by AFP

May 24, 2012 — Marine scientists studying life around deep-sea vents have discovered that some hardy species can survive the extreme change in pressure that occurs when a research submersible rises to the surface. ... full story

Jan. 24, 2012 — Microbiologists have found that the microbes that thrive on hot fluid methane and sulfur spewed by active hydrothermal vents are supplanted, once the vents go cold, by microbes that feed on the solid ... full story

Jan. 10, 2012 — Scientists have revealed details of the world's most extreme deep-sea volcanic vents, five kilometers down in a rift in the Caribbean seafloor. The undersea hot springs, which lie 0.8 kilometers ... full story

Sep. 13, 2011 — Ocean explorers observed two species of marine life scientists believe have never before been seen together at a hydrothermal vent -- chemosynthetic shrimp and tubeworms. They also observed the first ... full story

ScienceDaily features breaking news and videos about the latest discoveries in health, technology, the environment, and more -- from major news services and leading universities, scientific journals, and research organizations.